To provide a working machine for compost transportation, capable of improving the air transportation mechanism of compost by making the inner diameter of a flexible air transportation pipe approximately about 50 mm, uniformly placing a compost in a loosened state in an air flow and transporting the compost in a slightly floating state from the bottom of the flexible pipe.

This working machine for a compost transportation is equipped with a stirring auger 11 at the bottom of a compost hopper 10, a screw conveyor 12 below the auger and a rotary valve 5 between a compost outlet 10a of the compost hopper 10 and a compost inlet of a blending chamber 6 of compost and air flow. An air gate of the blending chamber 6 is disposed so as to approximately linearly pass the air flow sent from a blower 1 to the blending chamber 6 and to flow out the air flow from an air outlet. The blending chamber 6 is equipped with a compost inlet so as to drop the compost in an approximately vertical direction. The rotary valve 5 is laid above the compost inlet. A flexible pipe for air transportation is reinforced with a spiral wire to give a plastic flexible pipe reinforced with a spiral wire of 40-60 mm inner diameter. The plastic flexible pipe is detachably connected to the outlet of the blending chamber 6 of compost and air flow and an air velocity in the flexible pipe is adjusted to ≥25 m to <45 m.